22 Journal of Agricultural Research voi. xviu. no. i 



To sum up the work on identification of compounds in sorghum juice 

 the followdng list is given : 



Sugars: 



Sucrose. 



Dextrose. 



Levulose. 

 Organic acids: 



Aconitic. 



Citric. 



Malic. 



Tartaric, 



Oxalic. 

 Polysaccharides: 



Starch. 



Galactans (in gums). 



Pentosans (in gums). 



Xylose (in cellulose of pith). 

 Nitrogenous compotmds : 



Protein. 



1-Leucin. 



d-1-Asparagin. 



Glutamin. 



Cystin (?). 



Aspartic acid (?). 



(3) Distribution of sugars. — From the practical standpoint, it is 

 of importance to know the relative concentration of sugars in the various 

 joints of the cane, since it may be unprofitable to mill the whole stalk; 

 and from the standpoint of the physiology of the plant it is of interest 

 to know how the concentration of sugars indicates the relative maturity 

 of the various joints. 



It is important to know also the sugar content of the leaves and of the 

 suckers. It has been conclusively shown by many investigators (5, p. 

 142; jg, p. 65) that there is considerable sugar in the leaves but that the 

 purity of the juice (percentage of the total solids as sugars) is so low that 

 its sirup-making qualities are much inferior to those of the juice of the 

 cane. Since most cane is milled either with the leaves removed or when 

 the leaves are partially dried and hence contain but little extractable 

 juice, the question of the leaf juice is of little importance and will not be 

 dealt with further. The question of the juice of suckers, however, is of 

 more importance, since under some conditions sorghum suckers badly; 

 and when a corn binder is used for harvesting, the sucker canes are 

 included. Here again many analyses are on record which show consist- 

 ently that the suckers have a composition very similar to that of the 

 main canes at the same stage of maturity. Since the suckers are 

 always several stages behind the main canes in development, and 

 since the maturity of a plot is judged by the seed heads of the 

 main canes, the effect on the juice of cutting the two at the same 



